English
The integers ℤ form a FloorRing with floor and ceil given by the identity function.
Русский
Целые числа ℤ образуют FloorRing, у которого floor и ceil совпадают с тождественной отображением.
LaTeX
$$$\text{FloorRing } \mathbb{Z} \text{ with } \text{floor} = \text{id},\ \text{ceil} = \text{id}$$$
Lean4
instance : FloorSemiring ℕ where
floor := id
ceil := id
floor_of_neg ha := (Nat.not_lt_zero _ ha).elim
gc_floor _ := by rw [Nat.cast_id, id_def]
gc_ceil n a := by rw [Nat.cast_id, id_def]